During the past few decades, Western culture has witnessed an enormous
explosion in the number of eating disorders reported among young women.
One such type of eating disorder is Butimia Nervosa. According to the DSM-IV
criteria it is characterized by recurrent episodes of binge eating, in
which the person experiences a feeling of "loss of control",and
recurrent compensatory behavior in order to prevent weight gain. Both of
these behaviors occur, on average, at least twice a week for three months.
In addition, self-evaluation is unduly influenced by body shape and weight.
Finally, there are two subcategories of bulimia. There is the purging type
in which the person regularly engages in self-induced vomiting or the misuse
of diuretics or laxatives. The other type is the nonpurging group in which
the person engages in other inappropriate compensatory behaviors rather
than self-induced vomiting, laxatives, or diuretics. (American Psychiatric
Association, 1993)
Several studies have focused on stress as one important variable in
the onset or occurrence of eating disorders such as bulimia. In addition,
they explore the different situations or events which bulin-fics consider
to be stressful and the various ways in which bulimics cope with these
stressors. In this paper I plan to evaluate the effectiveness of the following
related studies and attempt to answer the question, What is the role of
stress in the development of DuUnfia?
It is possible that bulimics may appraise potential stressors differently
from other individuals. For example, in comparison to nonbulimics, people
with bulimia may appraise the situation as being more stressful, less predictable,
less controllable, or less desirable. in addition, some studies indicate
that bulimics experience more frequent binge eating episodes during situations
which are considered to be more stressful. For example, Wolf and Crowther
(1983) studied indicators of binge eating episodes among undergraduate
women and found that perceptions of experiencing more stress in the past
year were positively related to increased severity of binge eating. However,
since stress only accounted for 6.3% of the binges it is difficult to conclude
that bulimics appraisals of the stressors were different. (Cattanach, 1988)
Some theories suggest that butimics may experience coping deficits.
Coping is generally defined as the cognitive and behavioral efforts to
manage environmental and internal demands and conflicts affecting a person
which exceed that person's resources. Coping responses are supposed to
modify the effects of potential stressors. It may be that when. stressors
act in combination with dieting, women who lack coping skills may be most
vulnerable to developing bufimia (Lacey, 1986). Another study found that
environmental stressors were indirectly related with bulimia, such that
coping acted as the mediating variable. However, the study did not discriminate
between the factors which precipitated and the factors which maintained
the disorder. Therefore, further research must be done to determine whether
coping is influencing bufimic episodes, whether bulimia is influencing
coping responses, or if this process is reciprocal. (Cattanach, 1988)
A study conducted by Lopez-Ibor (I 991) supports this finding and
suggests it is related to levels of serotonin
This study cites anorexia nervosa and bulimia nervosa as two well defined
clinical entities among the group of eating disorders. The psychopathological
differentiation of the two syndromes has a great importance for diagnosis
and therapy. Based on case histories the authors state that "the presence
of affective symptomology--depressive, but not exclusively--in the eating
behavior disorders in general and particularly in bulirnia nervosa, is
nowadays interpreted as unspecific emotional lability as a response to
stressing situations." The study indicates that bulimics may be deficient
in the ability to metabolize serotonin. This deficiency is manifested in
the form of binges with food containing high contents of carbohydrates.
In addition, high levels of serotonin seem to be associated with feelings
of safety, fullness, etc. (Lopez-lbor, 1991)
The first study which I plan to discuss was conducted by Rosen, Compas,
and Tacy. The study examined the relationship among stress, psychological
disorders, and eating disorders in adolescents.
Method.-
The subjects were girls chosen fi-om three independent boarding schools
located in the northeast region of the United States. The study was explained
in dormitory meetings and 162 of the 248 students present at the meeting
returned a signed consent form and a completed questionnaire. In addition,
143 of these individuals also returned the Time 2 questionnaire. To analyze
possible effects of attribution, the scores from Time I were compared to
those who participated at both times and those who only participated at
Time 1. The mean age of the participants was 15.9 years of age and the
sample was geographically diverse originating from 33 different
states.
The subects completed the questionnaires under supervision in their
dormitories in January (Time 1) and May (Time 2). Four months between testing
was selected so that data collections would coincide with the school semester
schedule,
Subjects completed the 26-item version of the Eating Attitudes Test
(EAT) which taps into the symptoms associated with eating disorders. For
example, binge eating, guilt over eating, preoccupation with eating and
weight, purging, etc. In addition., the participants completed the middle
adolescent version of the Adolescent Perceived Events Scale which asks
the individual to indicate which of 205 major and daily life events have
occurred during the last 3 months. Each event which has occurred is then
rated on a scale of desirability ranging from very undesirable to very
desirable and a scale for impact of the event, ranging from no impact to
extremely high impact. The weighted negative events score was calculated
as the sum of the products of the desirability ratings and the impact ratings
for the undesirable events.
Results:
The mean EAT score at Time I corresponds to the 67th percentile for
female adolescent norms. Using the cutoff score for the clinical range,
24.6% fell above this level at Time 1. Therefore, the distributions for
this sample on the EAT were similar to or higher than the normative data.
The adolescents' Time I stress on the APES was not si@ficantly related
to the EAT at Time 1, r = .1 3, p =- .08. Conversely the correlation between
stress at Time 2 and eating disorder symptoms at Time 2 was significant
,r=.33,p<.001. This indicates that more stressful events were associated
with more severe eating disorder symptoms at that time. In addition, at
Time 2 the relation between stress and eating disorder symptoms was bidirectional.
Stress predicted increased eating disorder symptoms, and eating disorder
symptoms predicted increased stress. When the relation was examined over
a period of 4 months, stress was more a consequence of eating disorder
symptoms than vice versa. (Compras, 153-162) Although this study indicates
that stress and disordered eating are related, it was not mentioned whether
the eating disorder was displayed in the form of food restriction or binge
eating.
Another stu eating dy linking disorders with stress was conducted
by Cooper and Steere. It focused on the effects of anxiety on eating
behavior. The Study compared the amounts eaten by restrained and
unrestrained eaters following an anxiety-induction procedure.
Method.
The experiment consisted of several sessions and participants were paid
for their participation. During the sessions, participants were encouraged
to think about stressful, anxiety-producing events in their lives. Afterwards,
the participants were offered to help themselves to a buffet. In addition,
the participants' perceived level of hunger was assessed at the time.
Results:
Results showed that unrestrained subjects did not alter their eating
in response to either anxiety or hunger. When relaxed, restrained subjects
ate more when hungry than when not hungry. This finding is in agreement
with previous studies. (Herman, 1987) However, in the restrained subjects,
anxiety appeared to counteract the disinhibiting effect of hunger. When
perceived hunger was relatively weak, anxiety did not affect the consumption
of restrained subjects. However, when perceived hunger was strong, dietary
restrainers ate less when anxious than when relaxed. (Cooper, 1992)
A related study by Blundell (I990) confirms the relationship between
stressors and the resulting changes in eating patterns. In addition
it addresses the influence of internal processes with genetic, physiological,
and chemical foundation.
This study concerns the increasing occurrence of obesity over the past
50 years. It suggests that if low energy output by these persons cannot
be held totally accountable for this problem, then their energy input must
play a significant role. " Previously it was thought that emotional
disturbances led to overeating and becoming overweight. Today it is believed
that appetite is controlled by the interaction of internal (genetic, physiological,
and chemical) and external (environmental and psychosocial processes."
(Blundell, 1990) It further states that appetite (hyperphagia or hunger)
can be induced by changes in the brain neurotransmitters and nueromodulators,
altered metabolism, environmental stressors, etc.
Contrary to the previous studies which explored the relationship
between stress and eating disorders as a whole, this study focuses
primarily on binge eating, one characteristic of bulimia nervosa
Agras and Telch (1996) conducted this study to determine whether
emotional states influence binge eating in the Obese.
Objective:
The purpose of this study was to test the hypothesis that negative
affective states trigger
disinhibited eating in the form of binge eating for subjects with binge eating disorder (BED).
Method.-
Sixty females (30 with BED and 30 non-eating disordered) who responded
to advertisements for a study of eating, participated in the study. Subjects
who met the DSM-IV criteria for BED were considered for inclusion as were
overweight NED women. The NED women were eligible if they demonstrated
no evidence of binge eating, subjective sense of a loss of control over
eating, purging, and /or any behaviors that would meet the criteria for
an eating disorder not otherwise specified.
The procedure consisted of the BED subjects and weight-matched non-eating
disordered subjects attending a laboratory experiment during which they
were randomly assigned to a neutral or negative mood induction procedure.
Afterwards, the participants were served a multi-item buffet.
Results:
There were no differences between the BED and NED subjects on the
demographic data collected. The BED subjects averaged 43.8 years and the
NED subjects averaged 44.7. The average body mass index was 34.6 for BED
women and 32.2 for NED.
The results of an analysis of variance revealed significant main
effects for Mood and for Time and significant interaction effects at the
P>.OOI level. The results indicated that post-mood induction, participants
in the negative mood condition reported a significantly greater negative
mood affect than subjects in the neural mood condition.
There were no significant differences between the groups in the amount
of calories consumed at breakfast and lunch by the subjects in either mood
condition. The average buffet kilocalories consumed by BED subjects in
the negative mood condition was 1,053 kcal and 1,241 kcal for BED subjects
in the neutral condition. The NED participants consumed approximately 593
kcal and 628 kcal at the buffet in the negative and neutral conditions.
A significant main effect was found which indicated that BED subjects consumed
significantly more calories than NED subjects on both of the caloric measures.
Furthermore, a secondary hypothesis was proposed which predicted that BED
subjects who labeled the buffet eating episode as a binge would demonstrate
a more negative mood compared to BED subjects who labeled the episode as
overeating. This hypothesis was supported by a difference between the binge
group and the overeating group on the anxiety subscale which approached
significance at t = 1. 95, p<. 07. (Agras, 1996)
In addition to the studies mentioned, several other-studies have
been conducted concerning stress, bulimia, and binge eating behaviors.
For example, a case study performed by Chesler (1995) describes the
interaction between an anxiety disorder and an eating disorder. It showed
how the interplay between stress, fear of fatness, and panic disorder with
agoraphobia changed a patient's eating disorder symptoms from those of
bulima nervosa to food restricting. (Chesler, 1995)
The other study was conducted with tenth grade students to assess
the prevalence of purging behavior, alcohol and drug use, and reported
physical and psychological distress. The results indicated that female
purgers were more likely to report using alcohol to reduce stress than
nonpurging female peers. Also, when perceived situational control was low,
female purgers reported a higher level of psychological distress in comparison
to female nonpurgers. This information provides additional support for
the hypothesis that bulimics appraise stressors differently and it again
indicates a link between stress and eating disorders. (Killen, 1987)
Current research indicates that stress definitely plays a role in
bulimiaa. However, most of the findings are vague as to whether the bulimia
causes additional stress or whether stress instigates the onset of bulimia.
In addition, it is very difficult for studies to measure an individual's
experience of stress or anxiety since these are subjective feelings. Studies
have used tests such as the Adolescent Perceived Events Scale to try and
measure an individual's level of stress during a time period, However,
these scales may tend to give inaccurate results since different individuals
may experience and cope with stress differently. Therefore, additional
research in this area must focus on accurate measures of evaluating stress
levels and the causal relationship between stress and eating disorders,
whether stress leads to eating disorders or vise versa.
Agras, S. W. & Telch, C. F. (I 996). Do Emotional States Influence Binge Eating in the Obese? International Joumal ofeating Disorders, 20, 2 71-2 79.
American Psychiatric Association. (I 993). DSM-IV &aft criteria (3/l/93). Washington, DC: Author.
Blundell, J.E. (1990). Appetite disturbance and the problems of overweight. Drugs, 39, 1-19.
Cattanach, L.M. & Rodin, J. (1988). Psychosocial Components of the Stress Process in Bulimia. International Jourml of Fating Disorders, 7, 7 5 - 8 8.
Chesler, B.E. (1995). The Impact of Stress, Fear of Fatness, and
Panic Disorder with Agoraphobia on Eating Disorder Symptomatology: A Case
Study. International Journal of Eating Disorders, 18,195-198.
Compas, B.A., Rosen, J.C., & Tacy, B. (1993). The Relation Among
Stress, Psychological Symptoms, and Eating Disorder Symptoms: A Prospective
Analysis. International Journal of Eating Disorders, 14,153-162.
Cooper, P. J. & Steere, J. (I 993). The Effects of Eating of
Dietary Restraint, Anxiety, and Hunger. Intemational Journal of Eating
Disorders, 13, 211-219.
Lopez-lbor, A. J. (1991). The nosological entity buhmia nervosa. Actas
Luso-Espanolas de Neurologia, 19, 304-325.
Killen, J.D., Maron, D.J., Robinson, T.N., Saylor, K.E., Taylor,
C.B., & Telch, M.J. (1987). Evidence for an Alcohol-Stress Link among-
Normal Weight Adolescent's Reporting Purging Behavior. International Journal
of Eating Disorders, 6, 349-3 56.
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